A group of House Republicans threatening to block priorities from GOP senators who vote for the $1.7 trillion omnibus funding bill has grown to 31.

The 31 current and incoming members signing an open letter led by Rep. Chip Roy (R-Texas) to Republican Senate colleagues on Wednesday marks an increase from a similar Monday letter that had 13 names.

The new copy also made a direct reference to Senate Minority Leader Mitch McConnell (R-Ky.).

“The released legislative text confirmed this omnibus is an assault on the American people. As such, we reiterate that if any omnibus passes in the remaining days of this Congress, we will oppose and whip opposition to any legislative priority of those senators who vote for its passage – including the Republican leader,” the letter said. 

“We will oppose any rule, any consent request, suspension voice vote, or roll call vote of any such Senate bill, and will otherwise do everything in our power to thwart even the smallest legislative and policy efforts of those senators.”

Additional Republicans signing on to the Wednesday letter include Reps. Diana Harshbarger (Tenn.), Barry Moore (Ala.), Lauren Boebert (Colo.) and Marjorie Taylor Greene (Ga.), and Reps.-elect Keith Self (Texas) and Eric Burlinson (Mo.). 

It also includes several departing members who will not have any power over Senate votes next year: Jody Hice (Ga.), Mayra Flores (Texas), Louie Gohmert (Texas) and Yvette Herrell (N.M.).

The second letter urging opposition to the omnibus comes after House Minority Leader Kevin McCarthy (R-Calif.) endorsed the threat to thwart those bills on Tuesday, pledging that bills from GOP senators who vote for the omnibus would be “dead on arrival” if he is Speaker.

McCarthy is facing opposition to his candidacy for Speaker from many of those who signed the letter, though others support him.

Senators dismissed the threat on Tuesday.

“The reality is this kind of chest thumping and immaturity doesn’t instill confidence in their ability to lead. Now, maybe it helps Kevin get elected Speaker,” said Sen. Kevin Cramer (R-N.D.).

McCarthy attended a Senate GOP lunch on Wednesday to lobby against the omnibus, but sources told The Hill at the time that his rhetoric was largely toned down from his public statements.